Diaphragm signal



June 1 1926.

P. H. WITHINGTON DIAPHRAGM SIGNAL Filed March 30, 1923 l as steel, ofwhich the diaphragm is formed.

till

diaphragm Patented dune l, 1926,

'mrn" PHILIP H. VTITHINGTQN, U15

CLEVELAND, OHIU, ASSIGNOR TO THE SPARKS-WITHINGl- TQM CQMEAHY, 0FEACKSGN, MICHIGAN, .A CORPORATION OF (EH10.

nrarnnaen srenari.

Application filed awn so, was. Serial No.628fi83.

lhis invention relates to a new and improved diaphragm signal and moreparticularly to the specific form and construction of the diaphragmthereof.

The main object of the invention is to effect a substantial saving ofthe material such Further, with this construction, buckling of thediaphragm ordinarily caused by the fact that the clamping surfaces arenot absolutely flat is practically eliminated,

Further, a comparatively small area of the edge of the diaphragm isclamped between the case sections and therefore, the is allowed to flexmore easily.

Qther objects and advantages relate to the details of form andconstruction of the apparatus, all as will more fully appear from thefollowing description, taken in connection with the accompanyingdrawings, in

which I t Figure 1 is an elevation of the diaphragm and front casesection showing the clamping bolts in section.

Figure 2 is a longitudinal section of the signal. V

Figure 3 illustrates the method of blanking the diaphragm from a stripof sheet metal.

In general form, the signal here illustrated is of a well known type,and construction, embodying a rear case section '1 of dished form and aof oppositely dished form, the edges or peripheries of the case sectionbeing substantially flat and adapted to receive between them the edge ofa diaphragm 3, preferably formed of sheet metal.

In the well known construction of diaphragm signals, the edge of thediaphragm is preferably separated from the clamping peripheries of thecase sections 1 an -2- by means of cork washers 14 or other suitableeries of the case sections and thru the clamping washers -14.'-. Withthe usual confront case section 2- Clamping bolts -15- are providedextending through the periphlar number of clamping bolts. The diaphragm3- as illustrated, is of peculiar and novel form. It is in generaloutline of polygonal form.

In this particular illustration which at present is deemedto constitutea preferred embodiment of my invention, the diaphragm -3 is generallyoctagonal with alternate sides of arcuate' form and alternate sides ofstraight form. The arcs of the'alternate arcuately shaped sides l-, -5,-6 and -7- are preferably as shown, portions of the circumference of thesame circle and the straight sides 8-, -9, -l0 and llare alternatelyarranged between the arcuate sections, and the surfaces 8 and -10- arediametrically opposite each other, while the surfaces 9' and -Tl1- arediametrically oppositeeach other, the two diameters being approximatelyperpendicular to each other.

lit will be noted that the diameter of the tions is considerably lessthan the diameter of the case section'1 or the case section 2, and thatthe arcuate edges of the sides l, -5, 6 and -7- are portions of thecircumference of a circle of somewhat less diameter than the circledefined by the outer side of the bolts .15 which bolts are themselvesconcentrically arranged about the center of the case sections 1- and 2,.Preferably these arcuate surfaces in tersect the bolts 15 substantiallyat a diameter of the bolts and peripheral grooves or recesses -12- areformed sides -4, 5-, 6 and stantially semi-circular form, and withdiameters a proximately the same as the diameters of't e bolts -15 so asto tightly receive a portion of the bolts, as for instance,

7 of subd substantially one-half of each bolt.

Further one of the arcuate sides, such as ]7-, is formed with apositioning or locating groove 13' for locating pin or stud 24- formedin connection with the case section 2.

For illustration, it is found that the diaphragm of this invention canbe made or blanked from a sheet 4%,?" in width where it now requires astripbf in width to produce a diaphragm as ordinarily manufacturedfor ahorn of the same size or with case sections of the same diameter. Thus,a material saving is eflected'inthe amount cooperation with a' Bilaround the edge thereof,

of material re uired because of the reduction in the wi th of the sheet,and at the same time, the dia hragm being shortened both laterally andlongitudinally of the strip, a greater number of diaphragms can beblanked from a strip of predetermined length and a very substantialsaving in this perhaps most expensive material of diaphragm signals iseffected.

The diaphragm -3 in the usual manneris provided with a wear piece -Q5 atsubstantially its central portion for co-oper ation with the rotary cam16 carried on the armature shaft 17- of an electric motor (not shown).The front case section in the usual manner may carry an amplifier orhorn 18 while the rear case section 1 may carry in the usual manner amotor-enclosing case l9.

Altho I have shown and described a specific form and construction ofdevice as constituting a perhaps preferred embodiment of my invention, Ido not desire to restrict myself to the various changes may be madewithin the scope of the appended claims.

I claim:

1. In a signal, the combination with two circular case sections andconnecting bolts arranged concentrically around the edge thereof, of adiaphragm having its outer edge clamped between the case sections andlying Within a circle defined by the outer side of said bolts, andgrooves in the edge of said diaphragm for receiving portions of thebolts.

2. In a signal, the combination with a circular case section andconnecting bolts extending through and arranged concentrically of adiaphragm of polygonal form with alternate sides of arcuate shape, andalternate sides substantially straight and bolt-receiving grooves in thearcuate shaped sides.

3. In a signal, the combination with a, circular case section andconnecting bolts extending through and arranged concentrically aroundthe edge thereof, of a dia phragm of polygonal form with alternate sidesof arcuate shape, alternate sides sub stantially straight,bolt-receiving grooves in the arcuate shaped sides, and the edgeof thearcuate sides lying within the circle defined by the outer side of saidbolts.

4. In a signal, the combination with two circular case sections andconnecting bolts arranged concentrically around the edge thereof, of adiaphragm having its outer edge clamped between the case sections andlying within a circle defined by the outer side of said bolts, groovesin the edge of said diaphragm for receiving portions of the bolts, thearcs of the arcuate sides formdetails of form, as

of a regular memes ing portions of the circumference of the same circle.

5. In a signal, the combination with a circular case section andconnecting bolts extending through and arranged concentrically aroundthe edge thereof, of a diaphragm of polygonal form with alternate sidesof arcuate shape and alternate sides substantially straight,bolt-receiving grooves in the arcuate shaped sides, the arcs of thearcuate sides forming portions of the circumference of the same circle.

6. In a signal, the combination with a circular case section andconnecting bolts extending through and arranged concentrically aroundthe'edge thereof, of a diaphragm of polygonal form with alternate sidesof arcuate shape, alternate sides substantially straight, bolt-receivinggrooves in the arcuate shapedsides, and the outer edge of the arcuatesides lying Within the circle defined by the outer side of said bolts,the arcs of the arcuate sides forming portions of the circumference ofthe same circle.

7. A diaphragm in the form of a regular polygon with alternate sidessubstantially flat and bolt-receiving grooves in the edge of the sidesbetween the substantially flat sides.

8. A diaphragm substantially in the form of an octagon having alternatesides formed with bolt-receiving grooves.

9. A diaphragm substantially in the form of an octagon having aplurality of its sides formed with bolt-receiving grooves.

10. In a signal, a diaphragm in the form polygon with alternate sidesarcuate, the arcs of the arcuate sides forming portions of thecircumference of the same circle, and bolt-receiving grooves in thearcuate sides.

11; In a signal, a diaphragm in the form of a regular polygon withalternate sides arcuate and alternate sides straight, the arcs of thearcuate sides forming portions of the circumference of the same circle,and boltreceiving grooves in the arcuate sides.- 12. In a signal, adiaphragm of octagonal form with alternate sides arcuate in form, thearcs of the arcuate sides forming portions of the circumference of thesame circle, and bolt-receiving grooves in the arcuate sides.

13. In a signal a diaphragm of octagonal form with alternate sidesarcuate in form, and alternate sides substantially straight, the arcs ofthe arcuate sides forming portions of the circumference of the samecircle, and bolt-receiving grooves in the arcuate sides.

In Witness whereof I have hereunto set my hand this 13th day of March.1923.

' PHILIP H. WITHIN GTON.

